Measuring Energy Balance in Mice from VO2/VCO2, Food Intake and Activity Data

Sponsored by:

InsideScientific is an online educational environment designed for life science researchers. Our goal is to aid in

the sharing and distribution of scientific information regarding innovative technologies, protocols, research

tools and laboratory services.

Thank you to our event sponsor

Activity

Feeding Drinking

Body Mass

Running Wheel

Sleep Detection

Food Access Control

Environmental Control

Calorimetric Assessment

Environmental Monitoring

Temperature & Heart Rate

Oxymax/CLAMS

Marta Fiorotto Baylor College of Medicine

martaf@bcm.edu

Chris Adams Columbus Instruments

chris.adams@colinst.com

Presenters:

Energy Expenditure Essentials

Chris Adams

Sales Manager,

Columbus Instruments International Corporation

Graham Lusk

Indirect Calorimetry Concept

“Nitrogen” In (VNi)

Oxygen In (VO2i)

Carbon Dioxide In (VCO2i)

“Nitrogen” Out (VNo)

Oxygen Out (VO2o)

Carbon Dioxide Out (VCO2o)

Air In (Vi) Air Out (Vo)

“Nitrogen” In (VNi)

Oxygen In (VO2i)

Carbon Dioxide In (VCO2i)

“Nitrogen” Out (VNo)

Oxygen Out (VO2o)

Carbon Dioxide Out (VCO2o)

Air In (Vi) Air Out (Vo)

Metabolic Equations - Basics

Vi and Vo are the input and output ventilation rates (LPM) O2i and O2o are the oxygen fractions at the input and output…

VO2 = ViO2i – VoO2o

VCO2 = VoCO2o – ViCO2i

RER = AND

Respiratory Exchange Ratio:(RER): RER is simply the ration between the carbon dioxide production and the oxygen consumption. This value is a ration and thus does not have a unit. The RER ratio is calculated before any units conversion, weight normalization, or effective mass correction.

Metabolic Equations - Basics

Vi and Vo are the input and output ventilation rates (LPM) O2i and O2o are the oxygen fractions at the input and output…

VO2 = ViO2i – VoO2o Because O2 is exchanged for CO2 during the process, Vi ≠ Vo

And because this exchange also displaces N2, Ni ≠ No

The Haldane Transform

Nx = 1 – O2 – CO2

Vo = Vi x

Given: O2in = 20.9180% O2out = 20.4992% Flow-in set at 0.500 LPM (Vin)

CO2in = 0.0433% CO2out = 0.4282%

Metabolic Equations – Example

Metabolic Equations – Example (Haldane)

N2in = 1 – O2in – CO2in N2in = 1 - 0.209180 - 0.000433 = 0.790387 N2out = 1 – O2out – CO2out N2out = 1 - 0.204992 – 0.004282 = 0.790726

Vout = Vi * (N2in / N2out) = 0.500 * (0.790387/ 0.790726) 0.499786 LPM

CO2in = 0.0433% CO2out = 0.4282%

VO2 = (Vin * O2in) – (Vout * O2out) = (0.500 * 20.918%) – (0.499 * 20.4992%) = 0.002137 LPM of O2

VCO2 = (Vout * CO2out) – (Vin * CO2in) = (0.499 * 0.4282%) – (0.500 * 0.0433%) = 0.001923 LPM of CO2

Metabolic Equations – Example (VO2, VCO2, RER)

CO2in = 0.0433% CO2out = 0.4282% Vout at 0.499786 LPM

= 0.001923 / 0.002137 0.8999

CO2in = 0.0433% CO2out = 0.4282% Vout at 0.499786 LPM

And… VO2 = 0.002137 LPM VCO2 = 0.001923 LPM

Metabolic Equations – Example (VO2, VCO2, RER)

normVO2 = (VO2 in ml per hour / Mass in kg)

= 128.22 / 0.0256 5008.6 ml/hr/kg

Therefore, if VO2 = 0.002137 LPM, and the mouse weighs 25.6g…

Metabolic Equations – Normalization

Normalization – allows for better comparison of metabolic rates between subjects of the same species but of varying sizes and composition

Metabolic Equations – Lusk Table

RER % of Total O2 Consumed By: % of Total Heat Produced By: Heat / Liter of O2:

Carb Fat Carb Fat (kJ) (kcal)

0.707 0.0 100.0 0.0 100.0 19.62 4.6862

0.750 14.7 85.3 15.6 84.4 19.84 4.7387

0.800 31.7 68.3 33.4 66.6 20.10 4.8008

0.850 48.8 51.2 50.7 49.3 20.35 4.8605

0.900 65.9 34.1 67.5 32.5 20.61 4.9226

0.950 82.9 17.1 84.0 16.0 20.87 4.9847

1.000 100.0 0.0 100.0 0.0 21.13 5.0468

Metabolic Equations – Heat per Liter of O2 vs. RER

From the Lusk Table, kcal per liter of O2 over RER The graph is nearly linear, best fit line slope yields an equation by which to calculate Calorific Value

Metabolic Equations – Calorific Value (CV) & Heat

CV (kcal/liter of O2) = 3.815 + (1.232 * RER)

= 3.815 + (1.232 * 0.8999) 4.9237 kcal/LO2

Given: RER = 0.8999 AND VO2 = 0.002137 LPM

CV (kcal/liter of O2) = 3.815 + (1.232 * RER)

= 3.815 + (1.232 * 0.8999) 4.9237 kcal/LO2

Heat (kcal/hr) = CV * VO2

= 4.9237 * 0.002137 * 60 minutes 0.63132 kcal/hr

CV (kcal/liter of O2) = 3.815 + 1.232x

= 3.815 + (1.232 * RER) 4.9237 kcal/LO2

Heat (kcal/hr) = CV * VO2

= 4.9237 * 0.002137 * 60 minutes 0.63132 kcal/hr

normHeat (kcal/kg/hr) = Heat / Body Mass in kg / Time in hours

= 0.63132 / .0256 24.6609 kcal/kg/hr

Metabolic Equations – Weir Heat Equation

Alternate equations (“user defined”) where: CV = Calorific Value in kcal/liter Heat = (CV1 * VO2) + (CV2*VCO2)

Heat = (CV1 * VO2) + (CV2 * VCO2) Default Weir Constants: 3.815 * VO2 1.232 * VCO2 VO2= 0.002137 LPM VCO2 = 0.001923 LPM

Heat = (3.815 * 0.002137 * 60 min) + (1.232 * 0.001923 * 60) 0.63131

Heat = (CV1 * VO2) + (CV2 * VCO2) Common Weir Constants: 3.9 * VO2 1.1 * VCO2 VO2= 0.002137 LPM VCO2 = 0.001923 LPM

Heat = (3.9 * 0.002137 * 60 min) + (1.1 * 0.001923 * 60) 0.62798

0.62798 vs. 0.63131

Simplified Calorimeter Diagram

Fresh Air Pump

Filter

Manifold

Valved Manifold

Sample Pump

Flow Controller

CO2 Sensor

Tube Drier

O2 Sensor

Ammonia Filters

Metabolic Measurement Cycle

1. Cages are measured sequentially

2. Each measurement consists of a SETTLE and MEASURE time

• The SETTLE time allows for purging old gas sample and for O2 and CO2 sensor response.

• The gas concentrations are averaged over the MEASURE time.

SETTLE SETTLE SETTLE SETTLE

E SETTLE

SETTLE

1 2 3 REF 1 2

CYCLE TIME

SETTLE

1. Electrochemical – best suited for small economical systems

2. Paramagnetic – most common, maintenance free, and reasonably fast performance

3. Zirconia (High Speed) – fastest scan rate, ideal for large number of subjects

Three Most common Oxygen Sensor Technologies

• Dumbbell suspended in a magnetic field twists as its exposed to oxygen

• A light source bounces off a mirror on the dumbbell to a light detector to monitor the twisting

• Electric current passes through the dumbbell to counter the twist and re-center the dumbbell, the amount of current necessary is proportional to the [O2]

Paramagnetic O2

• Maintenance free!

• No consumable element

• User programmable between 0-100%

• Scans at 90 seconds per chamber

• Fast, but not the fastest

• Sample air diffuses through a membrane

• Oxygen drives the chemical reaction in the fuel cell and creates a voltage

• Voltage is proportional to the [O2]

Electrochemical O2 Sensor

• High accuracy at a low cost

• Requires periodic replacement

• A bit on the slow side at a scan rate of 3 min. per cage

• Zirconium Dioxide conducts electricity at high temperatures

• Oxygen ions pass through Zirconia which generate a “Nernst Voltage”

• Voltage proportional to natural log of ratio between concentrations

• Fast response

Zirconia Oxygen Sensor

• Very fast scan rate at 50 seconds per chamber

• Expensive to buy

• Consumable element is also expensive to replace

• CO2 absorbs infrared light (4.255µM)

• IR light emitted at the target wavelength, through the sample gas, and the absorption is recorded by the detector

CO2 Sensor

• Nafion plastic selectively removes water vapor

• Sample air is never in contact with chemical drying agent

Hydroscopic Tube Dryer

Calorimeter Data

• Real time gas readings & differentials

• RER & heat calculations in real time

• Export as CSV

Fresh Air (Vi)(0.50-0.60 LPM)

Sample Out(0.400 LPM)

Overflow

Chamber Body

Validation Gas (Vval) (0.01 LPM)

O2o = (O2i * Vi) / (Vi + Vval)CO2o = ((CO2i * Vi ) + (CO2val * Vval)) / (Vi + Vval)

O2o = (O2i * Vi) / (Vi + Vval)CO2o = ((CO2i * Vi ) + (CO2val * Vval)) / (Vi + Vval)O2o = (O2i * Vi) / (Vi + Vval)

CO2o = ((CO2i * Vi ) + (CO2val * Vval)) / (Vi + Vval)

Calorimeter Validation

• CO2 infusion technique

• Precise injections of 20% CO2 simulates CO2 production

• 80% N2 displaces O2 to simulate O2 consumption

Calorimeter Validation

• CO2 infusion technique

• Precise injections of 20% CO2 simulates CO2 production

• 80% N2 displaces O2 to simulate O2 consumption

• Target is ~0.4% Δ and RER of 0.943

Food Intake: Center Feeder vs Overhead

Over-head Feeder

• Food in a familiar location

• Allows use of standard shoebox cage with bedding

• Low stress

• Uses pelleted food

• Easy maintenance

Over-head Feeder

• Vulnerable to foraging

• Limited spillage collection

• Feeder takes longer to settle

Center Feeder

• Minimal foraging

• Larger spillage reservoir

• Weight stabilizes faster

Center Feeder

• Food presented at the floor

• Food must be powdered or crushed

• No bedding

• Requires acclimation

• Based on time

• Based on mass

• Based on time and mass

Automated Food Access

• Based on time

• Based on mass

• Enter Energy value and limit based on “calories.”

• Based on time

• Based on mass

• Enter Energy value and limit based on “calories.”

• Yoked/Paired feeding

• Synchronous with metabolic data (.CDTA)

Feeding Data

• Synchronous with metabolic data (.CDTA)

• Asynchronous feeding event log (.BDTA)

• Periodic user-defined intervals (.FTDA)

Feeding Data

Activity Monitoring

• Synced with calorimetry data

• XTOT = all beam breaks in the X axis

• XAMB = strictly locomotor beam breaks

• ZTOT = rearing events

• Wheel = revolutions

Activity Data (low-res)

• Author: Allan Pack

• Sleeping bouts from inactivity data

• Validated by EEG/EMG

Inactivity (sleeping bouts)

• Allan Pack

• Sleeping Bouts

• Sleep bouts time stamped

• Sleep threshold is adjustable in 10s epochs

• Define light/dark cycle

Activity Data (high-res)

Oxymax Sleep Detection

• Allan Pack

• Sleeping Bouts

• XTOT = all beam breaks (ambulatory + stereotypic)

• XAMB = strictly ambulatory beam breaks

• ZTOT = rearing event

Activity Data (high-res)

• Spontaneous Exercise Activity

• Provides “Infinite floor space” for lower stress

• Revolutions synced with calorimeter

• High Res activity data

Running Wheel Activity

• Compare Data sets

• Rapid Screening

• Sharing

• Graph prep

• Quick Screening

CLAX Data Review & Stat program

• Rapid Screening

• Sharing

• Graph prep

• Quick Screening

• Compare multiple data sets

• Share data with collaborators

• Rapid Screening

• Sharing

• Graph prep

• Quick Screening

• Compare multiple data sets

• Share data with collaborators

• Stat analysis

How to Measure and Interpret Energy Expenditure and Metabolism in Mice

Marta Fiorotto, PhD

Associate Professor,

Pediatrics-Nutrition Baylor College of Medicine

1. Basics of energy metabolism and how to assess it

2. Examples of data generated with the CLAMS

3. Tips, best-practices, and suggestions

What are we going to cover today?

Basics of Energy Metabolism & How To Assess It

First Law of Thermodynamics

Energy can be neither created nor destroyed…

• However, energy can change forms, and energy can flow from one place to another.

• The total energy of an isolated system always remains the same.

Energy Consumed = Energy Expended + Energy Deposited

Metabolizable Energy Intake

Energy Deposited

Total Energy Expenditure

Energy Consumption

Metabolizable Energy Intake = Total Energy

Expenditure

Energy In

Δ BW = 0

Energy Balance

• There is no weight gain when energy intake and expenditure are equal

Energy Out

When energy intake is greater than energy expenditure, the excess is deposited as fat (and lean) resulting in weight gain.

Positive Balance

Energy In

When energy intake is greater than energy expenditure, the excess is deposited as fat (and lean) resulting in weight gain.

Positive Balance

Energy In

Total Energy Expenditure

Δ Δ Negative Balance

When energy intake is less than energy expenditure , the body mobilizes its energy reserves to meet the energy deficit and results in weight loss.

Negative Balance

When energy intake is less than energy expenditure , the body mobilizes its energy reserves to meet the energy deficit and results in weight loss.

CLAMS DATA

Metabolizable Energy Intake

ENERGY BALANCE

Food Intake

ME density of diet

(kcal or kJ/g diet)

Weight of food eaten Δ Metabolizable Energy density = Metabolizable Energy Intake

Metabolizable Energy

Metabolizable Energy content of a food is the “energy available for heat production (i.e., energy expenditure) and body gains”

Gross Energy Δ (Fecal Energy + Gaseous Energy + Urinary energy)

Nutrient Atwater Factors

kcal (kJ) /g

Protein 4 (17)

Fat 9 (13)

Carbohydrate

digestible 4 (17)

fermentable fiber 2.6 (11)

Alcohol 7 (29)

Energy Intake Food Intake ME content of diet

Energy Expenditure VO2 ,VCO2, RER, Heat

Body weight, fat and lean mass

Normalization Total and /kg BW

Body weight, fat and lean mass

Energy Deposited or Mobilized

Total Ein & Eexp

Consider contribution of Pox

For further discussion and instructions see: Tschöp MH et al. A guide to analysis of mouse energy metabolism. Nature Methods (2011) Dec 28;9(1):57-63.

CLAMS DATA

ENERGY BALANCE

Components of Total Energy Expenditure

• Basal metabolic rate ~ energy needed to sustain the metabolic activities of cells and tissues, and to maintain blood circulation, respiration, GI, and renal function.

Basal metabolism

Thermogenesis

Spontaneous and voluntary

physical activity

• Thermogenesis ~ energy expended to maintain body temperature.

• Thermic effect of food (TEF) ~ energy expenditure associated with the digestion and assimilation of food, ~ 10% TEE

• Physical Activity ~ energy expended for physical activity

Measuring Components of Total Energy Expenditure

• Basal metabolic rate ~ energy needed to sustain the metabolic activities of cells and tissues, and to maintain blood circulation, respiration, GI, and renal function.

Basal metabolism

Spontaneous and voluntary

physical activity

thermogenesis • RMR: Resting metabolic rate

Cannon and Nedergaard J Exp Biol 2011;214: 242

Thermogenesis

Protocol for Estimating RMR

• Acclimate mice to CLAMS

• Continue to monitor EE and activity for 7-9 hrs.

• Close feeders at LIGHTS ON (resting phase)

• Average lowest 2 values after 4-5 hrs of fasting

For greater discussion refer to: Speakman JR, Frontiers in Physiol 2013, 4: 34

Estimation of Activity Energy Expenditure

For greater discussion refer to: Speakman JR, Frontiers in Physiol 2013, 4: 34 Van Klinken et al., PLoS ONE 2012, 7: e36162.

• Activities vary in their energy cost and duration

• This is not straightforward with a multiplexed system!

• Compare treatment effects on spontaneous cage and running wheel activity

• Energy cost of locomotion can be estimated with a metabolic treadmill.

Estimation of Thermic Effect of Food

EE following a standardized meal consumed after a fast

(RMR+ Activity Energy Expenditure)

Even & Nadkarni, Am J Physiol Regul Integr Comp Physiol 303: R459, 2012 Speakman JR, Frontiers in Physiol 2013, 4: 34

Review examples of data from CLAMS experiments

Differences in weight gain… are not due to lower food intake

Ghsr -/-, Ghrelin Receptor null

younger older 0

younger older

Ma X, et al. (2011) Ablations of Ghrelin and Ghrelin Receptor Exhibit Differential Metabolic Phenotypes and Thermogenic Capacity during Aging. PLoS ONE 6(1): e16391.

younger older

Ma X, et al. (2011) PLoS ONE 6: e16391. Lin, et al. (2011) Aging Cell 10: 996

…but to greater energy expenditure

Assessing feeding behaviour

• Determine feeding bouts from high frequency food intake data

• Parameters that can be extracted: • Number of feeding bouts (meals) / day • Amount of food eaten per meal (and per day) • Duration of feeding bouts • Inter-meal interval length • Diurnal eating pattern

No difference in total intake

Young Older

Meal frequency

Young Older

Meal duration

Young Older 0

Inter-meal interval

From Lin et al., J Nutr. 2014 144:1349-55.

Altered feeding behaviour in Ghsr -/- mice • Define feeding bout: intake of 0.02g; balance stable for 10 sec

Young Older 0

WT Ghsr-/-

Food intake

0.15 *

Young Older

Meal size

Diurnal pattern of food consumption

Stashi et al., Cell Rep. 2014, 6:633.

• Peak feeding in Src2 -/- mice was advanced by approx. 85 min.

• This mirrored the phase-advanced shift in wheel running.

• SRC-2 is a critical positive regulator of the mammalian circadian clock.

Food Intake (g/h)

40-d-old 140-d-old

Cage Activity (counts/h) (X and Z dimensions)

Energy Expenditure (kcal/h) (normalized for lean and fat)

Fetal growth restricted Control

Fetal growth restriction promotes physical inactivity and obesity in female mice

Baker, et al., Int. J. Ob. (2015) 39: 98

Fetal growth restricted Control

Food Intake (g/h)

40-d-old 140-d-old

Cage Activity (counts/h) (X and Z dimensions)

Energy Expenditure (kcal/h) (normalized for lean and fat)

Fetal growth restriction promotes physical inactivity and obesity in female mice

Baker, et al., Int. J. Ob. (2015) 39: 98 Fetal growth restricted Control

counts/h

mdx Control P

Body Weight (g) 16.5 + 0.7 20.7 + 0.7 0.03

Energy Intake (kcal/d)* 11.0 + 0.7 11.3 + 0.4 NS

Activity (counts x 103/d) 26.32 + 3.89 54.39 + 3.89 <0.001

Total Energy Expenditure* (kcal/d)

11.0 + 0.5

10.5 + 0.3

Resting Energy Expenditure* (kcal/d)

9.0 + 0.4

8.4 + 0.2

Energy Balance (kcal/d) 0.44 + 0.16 1.03 + 0.16 0.05

*values are least square means adjusted for differences in FFM and fat mass +SE

Energy Expenditure in the Juvenile Mdx Mouse Model of Duchenne Muscular Dystrophy

Radley-Crabb, et al. (2014) PLoS ONE 9: e89277.

X-ambulatory

Cage Activity

0 5 10 15 20 25 0

P<0.001

Distance Run on Wheel

Control Treatment

Z-rearing

†, P<0.05 Exercise Effect

Running wheel and cage activity need not change in parallel

Mismatch between food Intake and energy expenditure observed in the composition of weight gain

0 5 10 15 20 25 0

P<0.001

Distance Run on Wheel

Control Treatment Running wheel Sedentary

week 1 week 2 week 3 0.0

0.5 2.5

4.0 †

Daily Food Intake adjusted for BW + SE

†, P<0.05 Exercise Effect

Fat Gained

Control Treatment 0.0

P<0.05, Treatment x Exercise

Wheel Running Parameters

Why are the mice not running?

*, Treatment, P = 0.03

Bout length

Values are means + SE n=8-14/group

Control Treatment

Bout frequency

* †, P<0.05 Control Wheel

Data collected in 10 sec bins; 1 bout = 4> revs/10 sec

“Sleeping”

Sedentary 0

*, P<0.01 Treatment

Pack AI et al., Novel method for high-throughput phenotyping of sleep in mice. Physiol. Genomics 2007 28:232

Automated Food Access Control

• Meal feeding

• Restricted feeding

• Pair-feeding • Reduces manpower need (and mistakes)

Benefits:

• Less interference with mouse cages

• Enables feeding at times that are biologically relevant to the mouse

• Multiple meals with restricted feeding protocols reduces stress

• Diurnal feeding patterns are equivalent in both groups in pair-feeding protocols.

Tips, best-practices, and suggestions

Acclimation

1. Single housing

2. No or different bedding

3. Powdered diet

4. Different feeders

Factors that change for the mouse:

Recommendation:

1. One week prior to start, singly house and feed powdered diet

2. Three days before start place in CLAMS cages

3. Collect data for 48 hours

Variability in data decreases with acclimation

1 2 3 4 5

40 60 80

100 120 140 160 180 200

Total Daily Activity

Days in CLAMS

1 2 3 4 5 6.5

Total Daily EE

Days in CLAMS 21.5 21.0 17.8 18.0 17.8 7.5 6.1 5.3 4.3 2.6

Days in CLAMS

Daily Food Intake

CV 1 2 3 4 5

16.2 13.8 8.7 8.3 5.1

Male, C57BL6, n=6, Body weight = 25.7 + 1 g (SD)

Means + 1SD Means + 1SD Means + 1SD

Animal-To-Animal Variability

• Some mice love to dig in their food and empty out their hoppers v. quickly

• Some mice never adapt and become very depressed, sleep, and don’t eat

• Small mice can squeeze under certain types of floors and get stuck

• Small mice sometimes can’t reach water; need long sipper tubes

• Some mice on restricted intakes learn to defeat the food access control

Important to recognize normal variability vs. “CLAMS-induced” variability

Recommend: 1. Monitor mice closely during measurements

2. Weigh before and after CLAMS

Environmental Variables:

1. Temperature should be monitored and constant (thermogenesis)

2. Inappropriate light exposure and noise can alter behaviour (activity, EE, etc)

Considerations for Experimental Designs

• When you have a multiplexed system, the frequency of EE measurements on individual mice will depend on the total number of mice.

• When doing pair-feeding studies, ensure “a priori” that the intakes of “master” mice (determinant of food intake for the pairing) are within the expected norm.

• Decide if you will need high frequency measurements, e.g., for feeding behaviour assessment. You can’t go back after the fact and get the data.

Considerations for Experimental Designs (cont.)

• To enable mice to have access to the feeder, but not so much that they sleep on top of it, the spacers should be customized for the size of the mouse.

• Sieve your diet to ensure that it has no lumps in it.

Considerations for Experimental Designs (cont.)

• The timing of the measurements relative to the appearance of the phenotype should be given careful consideration. Measurements after the phenotype has occurred could reflect an adaptation to the change rather than the cause.

• As it is likely that you may need to repeat an experiment in order to have adequate replicates, it’s important that all experimental groups are included in each batch. Animal, diet, environmental, and instrument variability can introduce batch-to-batch variability, and this can be statistically controlled for.

Thank You!

For additional information on the CLAMS for Rats and Mice and Oxymax Systems please visit:

http://www.colinst.com

Marta Fiorotto Baylor College of Medicine

martaf@bcm.edu

Chris Adams Columbus Instruments

chris.adams@colinst.com

InsideScientific is an online educational environment designed for life science researchers. Our goal is to aid in

the sharing and distribution of scientific information regarding innovative technologies, protocols, research

tools and laboratory services.

Measuring Energy Balance in Mice from VO2/VCO2, Food Intake and Activity Data

Science

Monitorovanie hemodynamiky –prečo Monitorovanie... · Bunky s DO2= VO2 KO2 debt = 0 Bunky s DO2< VO2 KO2 debt = nie kritický = RECOVERY Bunky s DO2< VO2 KO2 debt = kritický =

Sistema cardiovascular y respiratorio vo2

Errors in VO2 testing

Perhitungan VO2 Max

サージカルフェイスマスクを使用した走行が呼吸機 …subject Vo2 ml/min VCO2 ml/min VE l/min RR n/min VT l/min VE/VO2 ml/ml VE/VCO2 ml/ml HR beats/min Vo2 % A

Fisiologia vo2 max

Proposal Individu_Suplemen Hb VO2 Max

CGCT Newsletter Vo2

Life Science Journal 2014;11(9) · carbon dioxide output (VCO2), respiratory-exchange ratio (RER), and oxygen uptake (VO2) were continuously measured by a breath-by-breath gas-exchange

masa otot dan vo2 maks

Advances in VO2 Thermochromic Films

Monitoração do Gasto Energético com uso da Calorimetria ... lisiane.pdf · Quociente Respiratório (QR) = VCO2/VO2 . Calorimetria Taxa de Oxidação dos substratos Existem Diferenças

Pengukuran Vo2 Max

The Responses of VO2, VCO2, Substrate Utilization and

Trabajo de investigacion vo2 max

NUS - VO2 Practical

Cinética do VO2

VO2 Max Kuliah-Prof Kiyatno

Portafolio icc vo2

Proyecto darwin vo2